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Fluctuation Effect in Superconductivity in an Electron Model with d-Wave Attraction

Xin-Zhong Yan
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Abstract

On the basis of $t$-matrix approximation, we study the superconductivity in the tight-binding model with d-wave attraction. The low-lying collective modes are considered as the predominant long-range fluctuations in the system. The Green's function is obtained as an analytic solution to a cubic equation. The superconducting order parameter and the transition temperature are substantially reduced from the values of the mean-field theory. The results for the pseudogap parameter at $T_c$ are compared with experiments. The calculated phase boundary of the superconductivity can reasonably describe the experiment results for the cuprates. The results for density of states are presented.

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Xin-Zhong Yan. 2001-10-17. Fluctuation Effect in Superconductivity in an Electron Model with d-Wave Attraction. https://arxiv.org/abs/cond-mat/0107099

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